Damien, How do you purpose to "tweak" the universe without
delving into the nanoscale? Do you know what nanotechnology is
comprised of?

Do *you* know what nanotechnology is? You advertise yourself
as a nanotechnology enthusiast, so I'm surprised at your
apparent confusion here.

Your very own webpage states:

DEFINITION of NANOTECHNOLOGY: Technology based on
the manipulation of individual atoms and molecules
to build structures to complex, atomic
specifications, by means of mechanosynthesis.

Now, Damien is discussing imaginary, hypothetical techniques for
moving entire galaxies around and changing the shape of space and
time. Neither he nor I nor anyone on Earth has much of an idea as to
how this might be practically accomplished. But this much is sure:
such activites would require *really*, *really*, *REALLY* LARGE
amounts of energy and would be carried out over *really*, *really*,
*REALLY* LARGE volumes of space, and upon *really*, *really*, *REALLY*
LARGE quantities of matter.

This puts it at the complete far opposite end of physical scale
from nano-scale mechanosynthesis. For an example, our galaxy, the
Milky Way, is roughly 9,450,000,000,000,000,000,000,000,000,000
nanometers across. It has approximately 200,000,000,000 stars in it.
Our own Sun contains roughly 1,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000 atoms.

Nanotechnology operates on matter one atom or molecule at a time.
It's, um, *very highly unlikely*, that nanomechanical techniques will
ever be used for acting upon objects at the galactic scale.

Hope this helps,
-Anthony

Disclaimer: I'm a software mechanick, not an astrophysicist. I
cranked out these figures on a Postit based on constants published on
various websites. If anyone notices hideous errors in these figures,
let me know, since I am curious as to what they accurately are.